charger: Do not suspend when disconnecting from charger

The device should be power off when disconnecting from charger.
If the device enter to suspend, the device couldn't handle the power off
process. So the device shouldn't suspend to handle the power off at that time

Bug: 7429504
Change-Id: I9a0a60e53f315cd83550dc730a33bc7bd464ef67
diff --git a/charger/charger.c b/charger/charger.c
index 25b3b1a..353bdf0 100644
--- a/charger/charger.c
+++ b/charger/charger.c
@@ -704,7 +704,8 @@
         charger->next_screen_transition = -1;
         LOGV("[%lld] animation done\n", now);
-        request_suspend(true);
+        if (charger->num_supplies_online > 0)
+            request_suspend(true);